Real-time imaging of inflammation and its resolution: It's apparent because it's transparent*

The ability to directly observe leukocyte behavior in vivo has dramatically expanded our understanding of the immune system. Zebrafish are particularly amenable to the high-resolution imaging of leukocytes during both homeostasis and inflammation. Due to its natural transparency, intravital imaging in zebrafish does not require any surgical manipulation. As a result, zebrafish are particularly well-suited for the long-term imaging required to observe the temporal and spatial events during the onset and resolution of inflammation. Here, we review major insights about neutrophil and macrophage function gained from real-time imaging of zebrafish. We discuss neutrophil reverse migration, the process whereby neutrophils leave sites of tissue damage and resolve local inflammation. Further, we discuss the current tools available for investigating immune function in zebrafish and how future studies that simultaneously image multiple leukocyte subsets can be used to further dissect mechanisms that regulate both the onset and resolution of inflammation.

Automated summary

The ability to directly observe leukocyte behavior in vivo has greatly expanded our understanding of the immune system, and zebrafish are an ideal model for high-resolution imaging of leukocytes. Due to their natural transparency, intravital imaging in zebrafish can be done without surgical manipulation, making it suitable for long-term observation of temporal and spatial changes during inflammation. Real-time imaging in zebrafish has revealed important insights into neutrophil and macrophage function, and also discussed the tools available for studying immune function in zebrafish and future research directions in dissecting the mechanisms of inflammation onset and resolution.